Mecode

GCode for all

Mecode is designed to simplify GCode generation. It is not a slicer, thus it can not convert CAD models to 3D printer ready code. It simply provides a convenient, human-readable layer just above GCode. If you often find yourself manually writing your own GCode, then mecode is for you.

Basic Use

To use, simply instantiate the G object and use its methods to trace your desired tool path.

from mecode import G
g = G()
g.move(10, 10)  # move 10mm in x and 10mm in y
g.arc(x=10, y=5, radius=20, direction='CCW')  # counterclockwise arc with a radius of 20
g.meander(5, 10, spacing=1)  # trace a rectangle meander with 1mm spacing between passes
g.abs_move(x=1, y=1)  # move the tool head to position (1, 1)
g.home()  # move the tool head to the origin (0, 0)

By default mecode simply prints the generated GCode to stdout. If instead you want to generate a file, you can pass a filename and turn off the printing when instantiating the G object.

g = G(outfile='path/to/file.gcode', print_lines=False)

NOTE: g.teardown() must be called after all commands are executed if you are writing to a file. This can be accomplished automatically by using G as a context manager like so:

with G(outfile='file.gcode') as g:
    g.move(10)

When the with block is exited, g.teardown() will be automatically called.

The resulting toolpath can be visualized in 3D using the mayavi or matplotlib package with the view() method:

g = G()
g.meander(10, 10, 1)
g.view()

The graphics backend can be specified when calling the view() method, e.g. g.view('matplotlib'). mayavi is the default graphics backend.

All GCode Methods

All methods have detailed docstrings and examples.

• set_home()
• reset_home()
• feed()
• dwell()
• home()
• move()
• abs_move()
• arc()
• abs_arc()
• rect()
• meander()
• clip()
• triangular_wave()

Matrix Transforms

A wrapper class, GMatrix will run all move and arc commands through a 2D transformation matrix before forwarding them to G.

To use, simply instantiate a GMatrix object instead of a G object:

g = GMatrix()
g.push_matrix()      # save the current transformation matrix on the stack.
g.rotate(math.pi/2)  # rotate our transformation matrix by 90 degrees.
g.move(0, 1)         # same as moves (1,0) before the rotate.
g.pop_matrix()       # revert to the prior transformation matrix.

The transformation matrix is 2D instead of 3D to simplify arc support.

Renaming Axes

When working with a machine that has more than one Z-Axis, it is useful to use the rename_axis() function. Using this function your code can always refer to the vertical axis as 'Z', but you can dynamically rename it.

Installation

The easiest method to install mecode is with pip:

sudo pip install mecode

To install from source:

$ git clone https://github.com/jminardi/mecode.git
$ cd mecode
$ pip install -r requirements.txt
$ python setup.py install

Optional Dependencies

The following dependencies are optional, and are only needed for visualization. An easy way to install them is to use Canopy or conda.

• numpy
• mayavi
• matplotlib

TODO

• add pressure box comport to __init__() method
• build out multi-nozzle support
  • include multi-nozzle support in view method.
• factor out aerotech specific methods into their own class

Credits

This software was developed by the Lewis Lab at Harvard University.